Enantiomerically enriched amino acids, especially α-amino acids, are useful in the synthesis of enantiomerically pure bio-active compounds, as intermediates for pharmaceuticals and for inclusion in infusion liquors for parenteral nutrition. Large quantities of these amino acids, especially L-lysine, are also produced for feed additive compositions.
The resolution of mixtures of enantiomers of amino acids, e.g., racemates, via classical crystallisation techniques is a common method for the generation of enantiomerically enriched amino acids. Although there have been great efforts to create new methodologies which allow the synthesis of amino acids in pure form e.g. using biotechnology, the classical pathway is still of value for special amino acids which are not, or only poorly, generated by biotechnological methods (Izumi et al., Angew. Chem. 90:187 (1978); Hoppe, et al., Chemie in unserer Zeit 18:73 (1984)).